The present invention relates to a cleaning system for removing foreign material from a cooling slot surface of a gas turbine rotor wheel, and particularly to a cleaning system which is applied from the exterior of the rotor wheel for cleaning the cooling surfaces along the cooling slot along the underside of the dovetails.
Rotor wheels, e.g., for gas turbines, typically include a plurality of circumferentially spaced dovetails about the outer periphery of the rotor wheel defining dovetail slots therebetween. The dovetail slots receive corresponding dovetail shaped bases of buckets which carry the plurality of airfoils about the rotor wheel. The buckets or airfoils are often cooled by air entering through a cooling slot in the rotor wheel and through grooves or slots formed in the bases of the buckets. Typically, the cooling slot extends circumferentially 360° through the dovetails and the dovetail slots.
Gas turbine cooling slots are typically inspected via an eddy current testing methods. For acceptable eddy current test results, the areas of inspection must be clean and free of foreign materials, such as dust, rust, scale deposits, oil, grit and the like. There is therefore a need to clean one or more surfaces of the cooling slot without disassembly of the rotor and consequent turbine downtime.